Circuit interrupter construction



March 2, 1954 s. 1. LINDELL 2,671,142 CIRCUIT INTERRUPTER CONSTRUCTIONOriginal Filed Oct. 31, 1951 4 Sheets-Sheet 1 IN V EN TOR.

March 2, 1954 Original Filed Oct. 31, 4 Sheets-Sheet 2 INVENTOR.

Jgardflafidell, BY

s. l. LINDELL 2,671,142 CIRCUIT INTERRUPTER CONSTRUCTION March 2, 1954s. I. LINDELL 2,671,142

CIRCUIT INTERRUPTER CONSTRUCTION Original Filed Oct. 31, 1951 4Sheets-Sheet 3 Z.9 jj

IN V EN TOR.

March 2, 1954 s. 1. LINDELL CIRCUIT INTERRUPTER CONSTRUCTION 4Sheets-Sheet 4 Original Filed Oct. 31, 1951 w l v w mw wmm

E hThT) w a w/ vw awm d5 ZIIIZIIIIZIMZ Patented Mar. 2, 1954 2,671,142CIRCUIT IN TERRUPTER CONSTRUCTION Sigurd I. Lindell,

Chicago, IlL, assignor to S & C

Electric Company, Chicago, III., a corporation of Delaware Continuationof application Serial No. 254,036,

October 31, 1951.

1953, Serial No. 362,891

25 Claims. (Cl. 200-146) This invention relates, generally, to electriccircuit interruptersand it has particular relation to circuitinterrupters for disconnecting under aload a conventional circuitisolating or switching device, such as a disconnecting fuse, adisconnecting switch or the like, without drawing'anarcbetweentheenergized parts thereof whichare separated or disconnected as anincident to the-circuit isolating operation as usually attempted ,tobeeffected by a lineman by means of a-switchstick, This application is acontinuation of application Serial No. 254,036, filed OctobenSl, 1951,and now abandoned.

It is-sometimes necessary-to deenergize a high voltage electricpowercircuit carrying load currentby swinging-a pivotally mounted fuseto open circuit position withoutrupturing its fusible element. Or itmaybe necessary to accomplish this by; opening the blade of a conventionaldisconnecting switch under these conditions, the switch blade having noparticular means for interrupting the arc incident toits being opened.When these operationsare performed, an arc is drawn between theenergized parts last in engagement since, under the assumed conditions,load current or line current is flowing. The are is likely tocausesevereburning of these parts or it may jumpstoground or to anadjacent circuit and createa fault causing damage. At any event it islikely that operation of one or more circuit interruptersicloser tothepower source will be required inorder to clear the fault thus caused.Accordingly, among the objects of this invention area To provide forsimply, efficiently and economically opening'an energized currentcarrying highvoltage electric power circuit by swingingafuse-ordisconnecting switch blade toopen position without, rupturing thefusible element of the-,former'and, without causingthe are between theenergized parts of the fuse or the switch lasttoseparate; to shunt theseparable parts of the fuse or; switch by an auxiliary circuitinterrupter that isarrangedto draw and extinguish the are within itselfafterthe parts of the fuse or disconnecting switch-or other circuitbreaking device have been separated, to extinguish the are quickly andpositively within the auxiliary circuit interrupter withoutexternalarcing; to construct the auxiliary circuitinterrupter so it can beconnected conveniently and quickly to the fuse or disconnecting switchand operated first to swing the fuse-or switch towardopen circuit pesitin while shunting; the separable energized parts thereof andconnectingthe contact-sol" the auxil iary circuit interrupter in seriestherewith and thereafter opening the. circuit by drawing and hisapplication June 19,

extinguishing an are within the auxiliary Cl1-" This invention isdisclosed in the embodiment accompanying drawings,-

thereof shown in the and it comprises the features of construction,combination of elements and arrangement of parts which will beexemplifiedin the construction hereinafter set forth and the scope ofthe application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of thisinvention, reference may be had to the following detaileddescription'taken together with the accompanying drawings, in which:

Figure 1 is a view in side elevation of a conventional form of dropoutfuse construction such as that described in States Patent No. 2,247,700,issued July 1, 1941,

certain partsof the terminal assembly at the upper endbeing broken awayin order to illustrate the details of construction;

Figure 2 is a top plan View of the circuit isolating device-or dropoutfuse shown in Figure 1;

Figure 3- is a view, in side elevation, of the dropout fuse constructionin Figure 1, at a reduced scale, and illustrating the application of theauxiliary circuit interrupter of the present invention thereto foreffecting ing between the parts thereof last to separate;

Figuregiand 5 are Views, similar to Figure 3,

showing successive stages in the opening of the fuse or disconnectingdevice by means of the auxiliary circuit interrupter;

Figure 6 is a view at an enlarged scale, certain parts being brokenaway, illustrating the general construction and arrangement of theauxiliary circuitinterrupter, the view being taken lookingfrom right toleft with respect to the auxiliary circuit interrupter as illustrated inFigures 3, 4,

and 5;

Figure 7 is a longitudinal sectional View of the the separable conmoredetail in Ramsey Unitedthe opening of the fuse or disconnecting devicewithout causing arc 3 but illustrating the relative positions of theparts of the auxiliary circuit interrupter when its separable contactsare in the full open position; and

Figure 10 is a view, in side elevation, of a modified form of contactarm for gripping the pull ring of the fuse, disconnecting switch or thelike.

Referring now particularly to Figure l of the drawings, it will beobserved that the reference character I designates, generally, a circuitisolating device or switching device which, in this instance, is adropout fuse construction such as described in more detail in RamseyPatent No. 2,247,700, issued July 1, 1941, and referred to above.However, it will be understood that the present invention can be used inconjunction with other circuit isolating devices, such as disconnectingswitches in which a switch blade is swung from the closed to the openposition for the purpose of introducing an air gap into the circuit.

The particular dropout fuse construction I0 includes an insulator IIwhich carries terminal assemblies I2 and I3 at its ends for connectionto line conductors as will be understood readily. Pivotally mounted atI4 on the lower terminal assembly I3 is a fuse tube that is indicated,generally, at I5. The fuse tube I5 contains a fusible element which isarranged to be ruptured on flow therethrough of excess current andmechanism is provided for automatically unlatching the fuse tube I5 fromthe upper terminal assembly I2 so that it can fall to the open circuitposition. When this occurs, the circuit is interrupted within the fusetube I5 and the arc incident thereto is extinguished. Ordinarily underfault conditions, the circuit will be interrupted within the fuse tubeI5 before it swings out of contact with the upper line terminal assemblyI2.

The present invention has to do particularly with the provision ofmechanism for effecting the opening of the circuit under load by bodilymoving the fuse tube IE to the open circuit position while it stillcontains a fuse link that has not been ruptured by overcurrent.Provision is made for accomplishing this while load current is flowingthrough the fuse tube I5 in such manner that no arc is drawn between itand the upper terminal assembly I2 during the circuit opening operation.

At its upper end the fuse tube I5 has a fuse tube terminal assemblyindicated, generally, at I6. This assembly includes a sleeve I! that isslidable upwardly relative to the fuse tube iii and formed integrallywith the sleeve I! is a hook is which is held in latching engagementwith a roller I9 carried by the upper terminal assembly I2. When thefuse link within the fuse tube 55 is ruptured, the sleeve IT is movedupwardly to such position that the hook I8 no longer engages the rollerI9. This same operation can be accomplished by means of an operating arm20 which is pivoted at 2i on the fuse tube terminal assembly I6. At itsouter end the operating arm 20 has a pull ring 22 which is arranged tobe engaged bythe prong of a switch stick or the contact arm of theauxiliary circuit interrupter to be described hereinafter. When the pullring 22 is swung in a counterclockwise direction about the pivot 2I, thesleeve I1 is moved upwardly so that the hook I8 clears the roller I9.The fuse tube I5 then can be swung or allowed to fall to the opencircuit position.

When the fuse tube I5 is operated in the manner just described by theprong of a switch stick 4 engaging the pull ring 22, an arc will bedrawn between the portions of the terminal assembly I2 and fuse tubeterminal assembly I6 last to separate. As indicated above, such an arcmay damage severely these terminal assemblies or it may cause a fault onthe circuit. In accordance with the present invention, the fuse tube I5can be unlatched from the upper terminal assembly I2 and swung to theopen position without drawing an are between the terminal assemblies I2and lb. The manner in which this is accomplished, generally, is byproviding a shunt circuit between the terminal assemblies I2 and I6,unlatching the fuse tube terminal assembly I6 from the upper terminalassembly I2, swinging the fuse tube I5 to such a position that an airgap is provided between the terminal assemblies I2 and I6 and theninterrupting the circuit by separating contacts within the auxiliarycircuit interrupter under such conditions that the arc is confined andextinguished quickly. The only modification required in the constructionof the circuit breaker It for accommodating the auxiliary circuitinterrupter comprises providing the sleet hood 23, forming a part of theterminal assembly I2, with a transversely extending conducting arm 24.As will appear hereinafter, this provides a fixed support for theauxiliary circuit interrupter while it is being employed for swingingthe fuse tube IE to open position without arcing between the terminalassemblies I2 and I6.

For the purpose of operating the dropout fuse IE to the open positionwithout arcing, a generally tubular auxiliary circuit interrupter, showngenerally at 25, is provided. Its application to the dropout fuse in isillustrated in Figure 3 and the details of construction are shown moreclearly in Figure '7 to which reference now will be had.

It will be noted that the auxiliary circuit interrupter has a relativelyfixed conducting member 26 at its upper end to which a metallic cap 21is secured by cap screws 28. A conducting eye member 29 is pivoted orswiveled at 30 on the metallic cap 21, and it comprises a pair ofresilient contact extensions (H which are bowed outwardly as indicatedat 32 for facilitating entry of the transversely extending conductingarm 24 carried by the sleet hood 23. 'In order to provide good contactengagement with the conducting arm 24, the upper portions 33 of theextensions 3I are positioned in side by side relationship and biasedtoward each other by the inherent resiliency of the contact extensions31. Because of this construction, they grip the conducting arm 24tightly therebetween. The upper ends 34 of the contact extensions 3i areturned outwardly, as shown, and interfit with a keeper 35 which not onlylimits the movement apart of the upper portions 33 but also serves as astop to prevent relative movement between the eye member 29 and theconducting arm 24 when a downward pull is applied to the auxiliarycircuit interrupter 25 in a manner to be described.

Depending from the relatively fixed conducting member 26 is aninsulating sleeve 38. It may be formed of a suitable phenoliccondensation product. Intermediate the ends of the insulating sleeve 38is a ringlike contact as that is electrically and mechanically connectedby a conducting sleeve it to the conducting member 25 at the upper endof the insulating sleeve 3%. It will be observed that both theinsulating sleeve 38 and the conducting sleeve iii! are threaded intothe underside of the conducting member 26. Cooperao'ruma:

ating withthe. ringliket contact: 39.:isa rodlike. contact. 4! having: abifurcatedtresilient {contact portion 42: at its. upper. end for.engaging-the. ringie likecontacttfi; Belowthe ringlike contact 38 isa.liner 43 of insulating material-.which is capable. of :evolving an 1are extinguishing medium. when subjected to. the heat of. the; 'arc. maybe formed of astackotfibre rings: or; other suitablesmaterialfor thispurpose: With-a view to. restricting: the area within whichxthexarc: canplay: between the contacts 3.9: and v 4 l. when they are-separated,aninsulating. trailer 44 is:.connectedrto...th'e. rodlike contact-4.1.and arranged tolbe. moiredconjointly therewith into thebore; formed. by.the liner 43: of insulating. material;

The trailer-.44 is also. formedof .a material which.

evolvesian arc: extinguishing medium. For ex ample. it may be formedotmethyl 'methacrylate resin; Ports 45: are provided;inthe'conducting'member: 26. and. extend radially therefrom. for;

venting; the interior terrupter. 25 so that be builtup within itingoperation. The with a shoulder 46 spaced from its upper. end forcooperating with a. tubular stop member 4'i. that is carriedibyametallic fitting threaded into' the lower end of" the. insulating.sleeve 38': The stop member. 411-has anzint'urned lower end? portion49*whichcooperateswith the shoulder 46,. as .shown moreclearly-in'Figure 9 .ofv the=drawings,. to limit the downward movementof'the rodlike-contact 4!.

Provision is. madev for maintaining the rodlike, contacti 4linengagement: with the-ringlike contact-39 asshown in. the rodlikecontact. 4 l iszprovidedwitht ashoulde'rv 52; near its:.lower endwhichis arrangedto co.- operate with resilient fingers=53that'J-are:carried by and dependfrom themetallic-ntting 48'. A garter spring 54urgesltheir lower contact engagement with the underside of. the shoulder52':

of the auxiliary circuit induring. the; circuit: interrupt:-

is in engagement with the'ringlikecontact 39'; However, when sufficient.force isapplied to'the rodlike. contact, the shoulder 52"moves: down.-wardly to suchposition th 53ammoved out of engagement therewith, asshown in- Figure 8, whereuponthe rodlikecontact 4 I can movequickly-toward the open circuit: position.

It" is importanttdknow whether the contacts Wand-4i are in engagement orout: of'engagement. For this purpose an indicator 55 is employed.Asshown in Figure '7, it. constitutes.- an extension of the lower endoftherodlike contact 4|. Its indicating function willibe described: inmore detail hereinafter.

A flanged metallic fitting: 56' transverse pin 51 position just belowmetallic fitting 56 58; depending from the metallic fitting 48',forlimiting the upward movement ofthe rodlike contact 4| and positioningits'upper'end contact portion. properly with respect to the ringlikecontact 39.

Surrounding and telescoped with the insulating sleeve 38 and freelyaxially rotatable with re-- spect thereto is a metallic sleeve 59. Atits upper end the metallic sleeve 59 hasan end? ring 601 against theunderside of'which a coillcompression spring 61' reacts; It will; be;observed; that is secured. by: a

The. liner 43 destructive pressure will "not.

rodlike' contact 4 I is provided" Figure 7; For thispurpose surroundsthefingers 5.33 and; inturned ends into mechanical This construction.serves. to hold" the'rodllke contact 41 in the position where it'- atthe resilient finger to the rodlike contact 4|; at: a. the shoulder 52.This'flanged; cooperates with alspacersleevebear outwardly against theinner surface ofJthesleeve 591 At'the lower end of the metallic sleeve59.- there isa. closure; disc 63 which is provided with apertures. 84for venting the interior of. the auxiliary circuit-interrupter 25. Theclosure disc Ba also has a centralaperture through which the indicator55- projects and from which it may be withdrawn as shown in Figure 8'.

It is. desirable to limit the relative movement. apart ofthemetallicsleeve S'Eancl the insulating sleeve 38- and to preventaccidental reclosure. of:

the. contacts 39 and 4!. For this purpose, the: latter is provided withan annular slot 66 and the former: carries a detent 6? spring biased bya resilient arm 68 that is secured by a rivet 69 to the outer surface ofthe sleeve 59 near its upper end. The inner end of the detent, filridesover the surface of the insulating sleeve 38* until it: reaches theannular slot (-26. As shown in Figure 8; the detent 68- has movedthrough an opening 7.0 in the end ring 6i? and into the annular slot 6.6prior to the forcing of the shoulder 52 past the resilient fingers 53and separation of the rodlikecontact 41 from the ringlike contact 39where it prevents any further downward movement of the metallic sleeve59 with respect to the insulating sleeve 38. Should the downwardlyacting force applied. to the sleeve 59' be released, thedetent: 61.reposing in the annular slot 65, pro.- vents the spring (51 fromeiiecting accidental reclosure of the contacts 39 and 4!.

Intermediate the ends of the metallic sleeve 59" a metallic supportbracket '13 is clamped. Formed integrally therewith, Figure 6, is an'arm14 which is'arranged to receive a detachable fitting-15 mounted on theupper end of a live line w stick 16-. Ordinarily the liveline stick (6is a suitably seasoned and treated wood pole which hashigh insulatingqualities and is arranged to bemanipulated by a lineman on the ground;for operating various live line tools which are employed. for performingoperations on a circuit while the'conductors are energized at highvoltage. The fittingl'd'is clamped to the arm 14 by a-bolt- 17 and acooperating wing nut 78.

Since the fuse tube i5 swings in an are about the: pivot I4 and the pullring 22. moves therewith, provision is made for accommodating thisrelative movement of the pull ring 22 with re spect to the auxiliarycircuit interrupter 25; In accordancewith this invention, there isprovided a contact. arm, shown generally at 79, which is rockablymounted on the arm 74. For this purpose a shaft 89 is, employed and ithas formed integrally therewith a shoulder 84, Figure 7, whichcooperates with a stop pin 82. The shoulder 81 and stop pin 82' limitthe movement of the contact arm 19 in a clockwise direction but permitit' to-swing in a counterclockwise direction to the position shown bythe broken lines in Figure 7:. A torsion spring 83,,having one end 1 84.fastenedtothe arm 14-: and the-other end-8.5:

from the closed fastened to a flange 86 secured by a transverse pin 81to the outer end of the shaft 89, serves to bias the contact arm 19against the stop pin 82. If desired, the shoulder 8| and stop pin 82 maybe omitted and the spring 83 can be arranged to function as a centeringspring biasing the contact arm 19 to the position shown by the fulllines in Figure 'I and permitting it to swing therefrom in eitherdirection as may be required in the manipulation of the auxiliarycircuit interrupter 25.

Referring particularly to Figure 6, it will be observed that the contactarm i9 includes a shank 99 which is fixed on and carried by a head 9!which forms an integral part of the shaft 89. At its upper end the shank90 has a contact finger 92 extending at right angles with a bulbousouter end 93 to facilitate entry into the opening in the pull ring 22.With a view to maintaining electrical contact with the pull ring 22 acooperating contact finger 9% is employed. It extends parallel to thecontact finger 92 and has an inclined outer end 95 to facilitatecooperation with the pull ring 22. The contact finger 94 extends atright angles from and is carried by a sleeve 96 which is telescoped overthe shank 99 and which is biased upwardly by a coil compression spring91. Movement of the sleeve 95 with respect to the shank 99 is limited bya slot 98 in the sleeve 95 and a stop pin 29 extending therethrough fromthe shank 99.

It will be understood that the spring 33 transmits its force through thecontact finger 92 to bear against the inside of the pull ring 22. Wherethis contact engagement is sufiicient, particularly where the spring 33functions as a centering spring as described above, sufficient contactpressure is maintained against the pull ring 22 so that, if desired, thecooperating contact finger 94 and parts associated therewith can beomitted. In such case reliance is placed on the biasing action of thespring 83 for maintaining the desired contact engagement.

In Figure of the drawings, there is illustrated a modified contact armconstruction. As shown generally at N2, the contact arm is constructedso that the contact fingers thereoi bear radially outwardly against theopening of the pull ring 22. For this purpose there is provided a sleeve93 which is carried by the head 9| on the outer end of the shaft 89.Projecting at right angles from the sleeve E93 is a contact finger EMwhose outer end H95 is inclined upwardly to facilitate entry into thepull ring 22. Slidably mounted within the sleeve m3 is a shank 285having a transverse pin it! extending therefrom through a slot I98 inthe sleeve [93 to limit relative movement between the 96 and the sleeve33. The shank W6 carries a contact finger 599 at its upper end whichextends parallel to the contact finger 94 and has an inclined outer endH9 to facilitate entry into the opening of the pull ring 22. The contactfinger [99 also has a shoulder Hi which cooperates with the pull ring 22to maintain mechanical and electrical engagement therewith. A coilcompression spring H2 reacts between the upper end of the sleeve [95 anda washer H3 secured to the upper end of the shank I96 for biasing thecontact finger W9 upwardly so as to maintain good mechanical andelectrical contact engagement with the inner surface of the pull ring 22at diametrically opposite locations.

In operation the auxiliary circuit interrupter, carried by the live linestick 76 as illustrated in shank Figure 3, is manipulated so that theeye member 29 engages the conducting arm 24 on the sleet hood 23 and thecontact arm 19 engages the pull ring 22. This is facilitated by theswivel mounting of the eye member 29 and the fact that the metallicsleeve 59, to which the live line stick 16 is attached by the supportbracket 13, is rotatable with respect to the longitudinal axis of theauxiliary circuit interrupter, more particularly the longitudinal axisof the insulating sleeve 38. It will be understood that either form ofcontact arm 19 or Hi2 can be employed. When the auxiliary circuitinterrupter 25 is positioned as described, the contacts 39 and 4|therein are in engagement and the parts are positioned as shown moreclearly in Figure '7. A shunt circuit then is established between theupper terminal assembly I2 of the circuit breaker I0 and the fuse tubeterminal assembly 16 through the conducting arm 24, eye member 29,relatively fixed conducting member 26, conducting sleeve 49, contacts 39and ll, flanged metallic fitting 56, resilient contact fingers 62,metallic sleeve 59, support bracket 13, and contact arm 19 to the pullring 22.

Now the live line stick it is manipulated by pulling on it lengthwise tothe position shown in Figure 4. Since the support bracket 13 is fastenedto the metallic sleeve 59 and since the eye member 29 prevents movementof the insulating sleeve 38, the metallic sleeve 59 is moved away fromthe insulating sleeve 38, as shown in Figure 4, and compression of thecoil spring 62 is begun. However, the resilient fingers 53 are strongenough to hold the rodlike contact 4! against the force initiallyexerted by the spring 65 and thus, while the metallic sleeve 59 is beingmoved downwardly to the position shown in Figure 4, the contacts 39 andM remain in engagement completing the shunt circuit previouslydescribed. Since the contact arm 19, which is in engagement with thepull ring 22, moves downwardly with the metallic sleeve 59, asmanipulated by the live line stick 16, the arm 20 is operated so as tolift the sleeve IT and remove the hook l8 from engagement with theroller Hi. This is followed by a swinging movement of the fuse tube IEto the position shown in Figure 4. Because the shunt circuit ismaintained by engagement of the contacts 39 and M within the auxiliarycircuit interrupter 25, no arcing occurs between the terminal assembliesl2 and I6 when they separate.

As illustrated in Figure 5, the continued'manipulation of the live linestick 1'6 causes the fuse tube 15 to swing further away from the closedposition. This is accompanied by a further compression of the spring 6!.The metallic tube 59 is operated to the position shown in Figure 8 wherethe detent El enters the groove 96 and prevents further movement apartOr reverse movement. After this occurs and the spring 6| has beencompressed to a point where the force exerted by it is greater than therestraining force exerted by the resilient fingers 53 on the shoulder52, they are no longer capable of restraining downward movement of therodlike contact il. Alternatively the coil compression spring may becompressed to the solid position where the downward pull on the liveline stick it is transmitted directly to the flanged metallic fitting56. In either event, after the metallic sleeve 59 has been locked by thedetent 5'! against reverse movement; the rodlike contact 4| is moveddownwardly to the position shown in Figure 8 of the following the equalto or greater than'the voltage Furtherit willbe projects 'fromtheibottom of the metallic :sleeve 69 when the contacts anddl arein-engagecircuit interrupter '2 5 engage the eye member 29 fromtheconducting and the ringlike' contact 39. This eflects a 'correspondingextension of the arc. The trailer =4l movement of the rodlike "contact=4l'into the bore in'the liner 43 assists in extinguishing the arc in-amanner readily understood. At thistime the external'isoiating air gap:between the terminal assemblies I2 and I'Gandthe break distanceover'the insulating sleeve 38- are break distance between-the contacts39 and withinthe auxiliary circuit interrupter '25,'thereby avoidin'gthe likelihood of external fiashoverdue to high'recovery incident to thecircuit interruption. While the 'ro'dlike contact 4| is moving downwerdly through the metallic-sleeve 59, "contact engagement therebetween ismaintainedthrough the resilient contact fingers '62.

It-will be observed that'theindi'cator'55, as

shown in Figure 8 of the drawings, is totally enclosed by the metallicsleeve 59atthe time that the contacts 39 and 4| are first separated.

observed that the indicator 55 -rnent as shown in Figure '7. Also itwillbe noted that, when the contacts and are'in the fully opened position,the indicator again projects from the lower This provides apositiveindication to the .lineman of'the position of the'contacts 39 and 4|,

.so thathe has definite knowledge that they are :either in the fullyclosed or fully open position.

The lineman now manipulates the auxiliary in such manner as to dismember'26. This is facilitated by the fact that the metallic sleeve 59 isrotatable about the longitudinal axis of the device. Thereafter'hefurthermanipulates the auxiliary circuit interrupter 25 to disengage thecontact arm 19 from the pull ring 12. This allows the fuse tube l5 toswing to the full open position under the'infiuence of gravity.

For further use, the auxiliary circuit interrupter'25 .is restored tothe'closed position, shown in' Figure 7, by withdrawing the detent 61from the slot '66 "and allowing the metallic sleeve59 to'be moved by thespring 6] back over themsulating sleeve 38, thereby'operating therodlikecontact 4| back into contact engagement with the ringlike contact 39. Ofcourse,'this is accomplished only when the "device is removed entirelyfrom proximity'to an energized part of the electric power system.

Since certain further changes can bemade in the foregoing constructionand difierent embodimerits of the invention can be made withoutdeparting from the spirit'andscope thereof, it is intendedthat allmatter shown in the accompanying drawings and described hereinbeforeshall be interpreted as illustrative andnot in a limiting sense.

What is claimed asnew is:

l. Mechanism for opening a high voltage circuit isolating device such asa disconnecting fuse, disconnecting switch or the like, normallycarrying line current comprising, in combination, an auxiliary circuitinterrupter having a relatively fixedconducting member for attachment'to2.

end of the metallic sleeve 59.

ment to a stationary stationary energized 'conducting'part of-saidcircuit isolating device and a relatively movable conductingmemberadapted to-be carried-bye live line stick, a contact arm'onsa-idmovable member for attachment to a movable energized conductingpart of said circuit isolating'device, relatively fixed and movablecontacts in said circuit interrupter connected respectively-to :saidfixed and movable 'con'ducting'members, movepart therebetween.

4. The invention,as set forth in claim 2, wherein the contact armincludes a pair of contact fingers biased apart for gripping theinterior of a ringlike portionof the inovableenergized conducting part.

5. The invention, as set forth in claim 2,-wherein a-springcooperateswith thecontact arm-to bias the same to a predetermined position.

6. The inventioxras set'forth in claim 2,- in a stop is provided'forlimiting the swinging movement of the contact arm in one direction, anda spring cooperates with said contact arm to biasthe same against'saidstop.

7. Mechanism for opening a high voltage circuit insulating device,such-as a disconnecting fuse, disconnecting switch or the like, normallycarrying line current comprising, in combination, an auxiliary circuitinterrupter having'a relatively fixed conducting member for attachenergized conducting part of said circuit isolating device *and'arelatively movable conducting member adapted to beta!- ried by a liveline stick, means'rotatablvmounting said conducting members relativetoeach other, a contact arm on said movable member for attachment to amovable energized conducting part of said circuit isolating device,relatively fixed and movable contacts in-said circuit interrupterconnected respectivelyto said fixed and movable conducting-members,movement of said movable conducting'memberaway from 'said fixedconducting member efiecting separation of said movable energizedconducting part while maintaining a-shunt circuit therebetween throughll separation of said separable contacts to open the circuit, the firstmentioned means thereafter being detachable from said parts whereuponthe same are permitted to operate to full open circuit position.

9. Mechanism for opening a high voltage circuit isolating device, suchas a disconnecting fuse, disconnecting switch or the like, normallycarrying line current comprising, in combination, an auxiliary circuitinterrupter having a relatively fixed conduct ng member for attachmentto a stationary energized conducting part of said circuit isolatingdevice and a relatively'movaole conducting member adapted to be carriedby a live line stick, a contact arm on said movable member forattachment to a movable energized conducting part of said circuitisolating device, relatively fixed and movable contacts in said circuitinterrupter connected respectively to said fixed and movable conductingmembers, movement of said movable conducting member away from said fixedconducting member effecting separation of said movable energizedconducting port from said stationary energized conducting part whilemaintaining a shunt circuit therebetween through said contacts,operating means for effecting separation of said contacts when saidmovable conducting member reaches a predetermined position away fromsaid fixed conducting member, and indicator means cooperating with saidmovable contact for indicating by its position relative to saidauxiliary circuit interrupter whether said contacts are closed or open.

, 10. Mechanism for opening a current carrying high voltage circuitisolating device, such as a disconnecting fuse, disconnecting switch orthe like having a transversely extending conducting arm on a stationaryenergized conducting part and a pull ring on a movable energizingconducting part that is arranged to swing bodily through an arc fromclosed to open position, comprising, in combination; a tubular auxiliarycircuit interrupter having a relatively fixed conducting member at oneend, an insulating sleeve extending therefrom, a metallic sleevetelescoped over and movable endwise away from said insulating sleeve, arelatively fixed contact within said insulating sleeve connected to saidfixed conducting member, a rodlike contact engaging said relativelyfixed contact and movable endwise away therefrom through said insulatingsleeve, conducting means interconnecting said rodlike contact and saidmetallic sleeve during movement thereof relative to said insulatingsleeve, and a coil compression spring surrounding said insulating sleeveand reacting between said metallic sleeve and said rodlike contact tobias the latter out of contact engagement with said relatively fixedcontact on movement of said metallic sleeve away from said fixedconducting member; a conducting eye member carried by said fixedconducting member for engaging said conducting arm, a support bracketsecured to said metallic sleeve and having a part adapted to be mountedon a live line stick for manipulating said auxiliary circuit interrupterand parts associated therewith, and a contact arm rockably mounted onsaid support bracket.

11. Mechanism for opening acurrent carrying high voltage circuitisolating device, such as a disconnecting fuse, disconnecting switch orthe like having a transversely extending conducting arm on a stationaryenergized conducting part and a pull ring on a movable energizedconducting part that is arranged to swing bodily through an are fromclosed to open position, comprisin in combination; a tubular axiliarycircuit interrupter having a relatively fixed conducting member at oneend, an insulating sleeve extending therefrom, a metallic sleevetelescoped over and movable endwise away from said insulating sleeve, arelatively fixed contact within said insulating sleeve connected to andspaced from said fixed conducting member, a liner within said insulatingsleeve capable of evolving an arc extinguishing medium when subjected tothe heat of an arc, a rodlike contact engaging said relatively fixedcontact and movable endwise away therefrom through said liner and havingspaced shoulders thereon, resilient means carried by said insulatingsleeve for engaging said rodlike contact and cooperating with one ofsaid shoulders to hold said rodlike contact in engagement with saidrelatively fixed contact, conducting means interconnecting said rodlikecontact and said metallic sleeve during movement thereof relative tosaid insulating sleeve, a coil compression spring surrounding saidinsulating sleeve and reacting between said metallic sleeve and saidrodlike contact to bias the latter out of contact engagement with saidrelatively fixed contact on movement of said metallic sleeve away fromsaid fixed conducting member to a position where said spring is stressedsuificiently to move said one shoulder on said rodlike contact out ofrestraining engagement with said resilient means, and a stop membercarried by said insulating sleeve for cooperating with the othershoulder on said rodlike contact to limit the outward movement thereofunder the influence of said spring; a conducting eye member pivoted onsaid fixed conducting member for engaging said conducting arm, a supportbracket secured to said metallic sleeve and having a part adapted to bemounted on a live line stick for manipulating said auxiliary circuitinterrupter and parts associated therewith, and a contact arm rockablymounted on said support bracket.

l2. Mechanism for opening a current carrying high voltage circuitisolating device, such as a disconnecting fuse, disconnecting switch orthe like having a transversely extendin conducting arm on a stationaryenergized conducting part and a pull ring on a movable energizedconducting part that is arranged to swing bodily through an arc fromclosed to open position, comprising, in combination; a tubular auxiliarycircuit interrupter having a relatively fixed conducting member at oneend, an insulating sleeve extending therefrom, a metallic sleevetelescoped over and movable endwise away from said insulating sleeve, arelatively fixed ringlike contact within said insulating sleeveconnected to and spaced from said fixed conducting member, a linerwithin said insulating sleeve capable of evolving an arc extinguishingmedium when subjected to the heat of an arc, a rodlike contact engagingsaid relatively fixed ringlike contact and movable endwise awaytherefrom through said liner and having spaced shoulders thereon, aninsulating trailer movable with said rodlike contact through saidrelatively fixed ringlike contact and into said liner, resilient fingerscarried by said insulating sleeve for cooperating with one of saidshoulders to hold said rodlike contact in engagement with said ringlikecontact, conducting means interconnecting said rodlike contact and saidmetallic sleeve during movement thereof relative to said insulatingsleeve, a coil compression spring surrounding said insulating sleeve andreacting between said metallic sleeve and .said rocllike contact to biasthe latter out of contactengagement with said relatively fixed ringlikecontact on movement of said metallic sleeve. away fromsaid fixedconducting member to a. position where said spring-isstressed-sufiiciently'to movesaid one shoulderon said rodlike-contactout of restraining engagement with said resilient fingers, and a stopmember carried by said insulating sleeve for cooperating with the othershoulder on said rodlike contact to limit the outward movement thereofunder the infiuen'ce of said spring; a conducting eye member pivoted onsaid fixed conducting member and including resilient means for engagingsaid conducting arm, a support bracket secured to said metallic sleeve.and having apart adapted'to-be mounted on a live line stick formanipulating said auxiliary "circuit interrupter and parts:associatedtherewith, and a contact arm rockabl-y mountedon said supportbracket and including spring biased gripping means for engaging saidpull ring to establish both mechanical connection and electrical contacttherewith.

13. Mechanism for opening a current carrying high voltage circuitisolating devicesuch as a disconnecting fuse, disconnecting switch orthe like having a transversely-extending conducting arm on a stationaryenergized conductin part that is arranged to swing bodily through an'arcfrom closed to open position comprising, in combination; a tubularauxiliary circuit interrupter having a relatively fixed conductingmember at one end, an insulating sleeve extending therefrom, a metallicsleeve telescoped over and movable endwi'se awayfrom said insulatingsleeve, a ringlike contact within said insulating sleeve connected toand spaced from said fixed conducting member, a liner within saidinsulat'ng sleeve capable of evolving an arc extinguishingmedium whensubjected to the heat of an are, a rodlike contact engaging saidringlilte contactzand movable endwise away therefrom through said linerand having spaced shoulders thereon, an insulating trailermovable withsaid rodlike contact through said rin'glike contact and into said liner,resilient fingers carried by said insulating sleeve for cooperating withone of said shoulders to hold it-in engagement with said ringlikecontact, conducting means interconnecting said rodlilte contact andsaidmetallic sleeve during movement thereof relative to saidinsulatingsleeve; a coil 7 compression spring surrounding said insulating sleeveand reacting between said metallic sleeve and said rodlike contact tobiasthe latter out of contact engagement with said rin-glike contact onmovement of said metallic sleeve away from said fixed conducting memberto a position where said spring isv stressed 'sufiiciently to move saidone shoulder on said rodlike contact out of restraining engagement withsaid resilient fingers, and a stop member carried by said insulatingsleeve for cooperating with the othersh'oulder on said rodlike contactto limit the outward movement thereof under the influence of saidspring; a conducting eye member pivoted on said fixed conducting memberand including resilient means for engaging said conducting arm, asupport bracket secured tosaid metallic sleeve and having a part adaptedto be mounted onal-i-ve-line stick for'man-ipulating said auxiliarycircuit interrupter and partsassoci'ated--'therewith, and a contact armrockably 'mounted cn said support bracket and including spring biasedgripping means for engaging said-pull ring to establlsh bothmechanicalconnection and electrical :contact therewith.

l4. 'Mechanism for opening :a current carrying high voltage circuitisolating device, such as a disconnecting fuse, disconnecting switchorlthe like having a transversely extending conducting arm on astationary energized conducting part and a pull ring on amovableenergizedconducting part that is arranged to swingbodilythrough an arefrom closed to open position, comprising, in combination; a tubularauxiliary circuit interrupter having a relatively fixed conductingmember at one end, an insulating sleeve extending therefrom, a metallicsleeve telescoped over and movable end-wise away from said insulatingsleeve, a relatively fixed contact Within said insulating sleeveconnected to and spaced from said fixed conducting member, a rod-likecontact engaging said relatively fixedcontact and movable endwise awaytherefrom through said insulating sleeve and having spaced shouldersthereon, indicator means cooperating with said rod like contactandshowing when said contacts are engaged :and when fully disengaged,resilient fingers carried by said insulating sleeve cooperating with oneof said shoulders to hold it in engagement with said relatively fixedcontact, contact means interconnecting said rodlike contact and saidmetallic sleeve during movement thereof relative to said insulatingsleeve, a coil compression spring surrounding said insulating sleeve andreacting between said metallic sleeve and said rodlike contact to biasthe latter out of contact engagement with said relatively fixed'contacton movement of said metallic sleeve away from said fixed conductingmember to a position where said spring is stressed sufficiently to movesaid one shoulder on said rodlike contact out of restraining engagementwith said resilient fingers, a stop thereof under the influence of saidspring, and means cooperating with said insulating and metallic sleevesfor limiting movement thereof apart and locking them in releasedposition; a-c'onducting eye member pivoted on said fixed conductingmember and including resilient means for en*-= h gh voltage circuitisolating device, such as a ing part that is arranged to swing bodilythrough an are from closed toopen position, comprising, in combinationratubular auxiliary circuit interrupter' havinga relatively fixedconducting meminsulating sleeve extending tact means interconnectingsaid rodlike contact and said metallic sleeve during movement thereofrelative to said insulating sleeve, and a coil compression springsurrounding said insulating sleeve and reacting between said metallicsleeve and said rodlike contact to bias the latter out of contactengagement with said relatively fixed contact on movement of saidmetallic sleeve away from said fixed conducting member; a conducting eyemember pivoted on said fixed conducting member for engaging saidconducting arm and including a pair of contact extensions biased towardeach other for engaging said conducting arm therebetween under pressure,a support bracket secured to said metallic sleeve and having a partadapted to be mounted on a live line stick for manipulating saidauxiliary circuit interrupter and parts associated therewith, a contactarm rockably mounted on said support bracket, spring biased grippingmeans carried by said contact arm for engaging said pull ring toestablish both mechanical connection and electrical contact therewith,said contact arm being arranged to rock relative to said auxiliarycircuit interrupter on movement of said metallic sleeve away from saidfixed conducting member while the same is held stationary by interactionof said conducting arm and said eye member and said gripping means beingarranged to move conjointly with said pull ring as said energizedconducting part of said circuit breaker swings to the open position, anda spring interacting between said bracket and contact arm to bias thelatter to a predetermined position.

16. Mechanism for opening a current carrying high voltage circuitisolating device, such as a disconnecting fuse, disconnecting switch orthe like having a transversely extending conducting arm on a stationaryenergized conducting part and a pull ring on a movable energizedconducting part that is arranged to swing bodily through an are fromclosed to open position, comprising, in combination; a tubular auxiliarycircuit interrupter having a relatively fixed conducting member at oneend, an insulating sleeve extending therefrom, a metallic sleevetelescoped over and movable endwise away from said insulating sleeve, aringlike contact within said insulating sleeve connected to and spacedfrom said fixed conducting member, a liner within said insulating sleevecapable of evolving an arc extinguishing medium when subjected to theheat of an are, a rodlike contact engaging said ringlike contact andmovable endwise away therefrom through said liner and having spacedshoulders thereon, an insulating trailer movable with said rodlikecontact through said ringlike contact and into said liner, an indicatorextending endwise from said rodlike contact out of said metallic sleevewhen said contacts are engaged and when fully disengaged, resilientfingers carried by said insulating sleeve cooperating with one of saidshoulders to hold said rodlike contact in engagement with said ringlikecontact, contact means interconnecting said rodlike contact and saidmetallic sleeve during movement thereof relative to said insulatingsleeve, a coil compression spring surrounding said insulating sleeve andreacting between said metallic sleeve and said rodlike contact to biasthe latter out of contact engagement with said ringlike contact onmovement of said metallic sleeve away from said fixed conducting memberto a position where said spring is stressed sufiiciently to move saidone shoulder on said rodlike contact out of restrainmg engagement withsaid contact fingers, a stop member carried by said insulating sleevefor cooperating with the other shoulder on said rodlike contact to limitthe outward movement thereof under the influence of said spring, andspring biased detent means cooperating with said insulating and metallicsleeves for limiting movement thereof apart and locking them in releasedposition; a conducting eye member pivoted on said fixed conductingmember for engaging said conducting arm and including a pair or contactextensions biased toward each other for engaging said conducting armtherebetween under pressure, a support bracket secured to said metallicsleeve and having a part adapted to be mounted on a live line stick formanipulating said auxiliary circuit interrupter and parts associatedtherewith, a contact arm rockably mounted on said support bracket,spring biased gripping means carried by said contact arm for engagingsaid pull ring to establish both mechanical connection and electricalcontact therewith, said contact arm being arranged to rock relative tosaid auxiliary circuit interrupter on movement of said metallic sleeveaway from said fixed conducting member while the same is held stationaryby interaction of said conducting arm and said eye member and saidgripping means being arranged to move conjointly with said pull ring assaid energized conducting part of said circuit breaker swings to theopen position, a stop on said bracket limiting rocking movement of saidcontact arm in one direction, and a spring interacting between saidbracket and contact arm to bias the latter against said stop.

l7. Mechanism for opening a high voltage circuit by manipulation of alive line stick comprising, in combination, a circuit interrupter havinga relative fixed conducting member for connection to an energized partof said circuit and a relatively movable conducting member adapted to becarried by said live line stick and to be connected to a circuit to bedisconnected from said energized part, and relatively fixed and movablecontacts in said circuit interrupter connected respectively to saidfixed and movable conducting members, movement of said movableconducting member by said live line stick away from said fixedconducting member effecting separation of said contacts and therebydisconnection of said circuits.

18. Mechanism for opening a high voltage circuit by manipulation of alive line stick comprising, in combination, a circuit interrupter havinga relatively fixed conducting member for connection to an energized partof said circuit and a relatively movable conducting member adapted to becarried by said live line stick and to be connected to a circuit to bedisconnected from said energized part, relatively fixed and movablecontacts in said circuit interrupter connected respectively to saidfixed and movable conducting members, and operating means cooperatingwith said movable conducting member when the same is moved by said liveline stick away from said fixed conducting member and said contacts forseparating them with a snap action when said movable conducting memberreaches a predetermined position away from said fixed conducting memberwhereby said circuits are disconnected.

19. Mechanism for opening a high voltage circuit by manipulation of alive line stick comprising, in combination, a circuit interrupter havinga relatively fixed conducting member; for

, connection to an energized part of said circuit and a relativelymovable conducting member adapted to be carried by said live line stickand to be connected to a circuit to be disconnected from said energizingpart, relatively fixed and movable contacts in said circuit interrupterconnected respectively to said fixed and movable conducting members,operating means cooperating with said movable conducting member when thesame is moved by said live line stick away from said fixed conductingmember and said contacts for separating them with a snap action whensaid movable conducting member reaches a predetermined position awayfrom said fixed conducting member whereby said circuits aredisconnected, and are extinguishing means operating with said contactsfor extinguishing the arc therebetween on separation thereof.

20. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like, normallycarrying current and having a stationary normally energized terminalcontact member and a current carrying member movable into and out ofengagement therewith by manipulation of a live line stick, saidmechanism comprising, in combi" nation, an auxiiiary circuit interrupterhaving contact means for connection to said terminal contact member andadditional contact means for connection to said movable current carryingmember, said auxiliary circuit interrupter when closed providing a shuntcircuit between said terminal contact member and said movable currentcarrying member, said auxiliary circuit interrupter being adapted to becarried by said live line stick and to be manipulated by an operator todisengage said movable current carrying member from said terminalcontact member while said shunt circuit is maintained, and means foroperating said auxiliary circuit interrupts to open said shunt circuitafter said movable current carrying member disengages said terminalcontact member.

21. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like, normallycarryin, current and having a stationary normally energized terminalcontact member and a current carrying member movable in a plane into andcut of engagement therewith by manipulation or" a live line stick, saidmechanism comprising, in combination, an auxiliary circuit interrupterhaving contact means for connection to said terminal contact member andadditional contact means for connection to said movable current carryingmember, said auxiliary circuit interrupter when closed providing a shuntcircuit between said terminal contact member and said movable currentcarrying member, said auxiliary circuit interrupter being adapted to becarried by said live line stick and to be manipulated by an operator todisengage said movable current carrying member from said terminalcontact member while said shunt circuit is maintained, the connectionsbetween said auxiliary circuit interrupter and said terminal contactmember and between said auxiliary circuit interrupter and said movablecurrent carrying member being suificiently flexible to allow themanipulation of said live line stick with a substantial range ofmovement in planes other than said plane of movement of said movablecurrent carrying member and planes parallel thereto, and means foroperating said auxiliary circuit interrupter to open said shunt circuitafter said movable current carrying member disengages said terminalcontact member.

22. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like, normallycarrying current and having a stationary normally energized terminalcontact member and a current carrying member movable in a plane into andout of engagement therewith by manipulation of a live line stick, saidmechanism comprising, in combination, an auxiliary circuit interrupterhaving contact means for connection to said terminal contact member andadditional contact means for connection to said movable current carryingmember, said auxiliary circuit interrupter when closed providing a shuntcircuit between said terminal contact member and said movable currentcarrying member, said auxiliary circuit interrupter being adapted to becarried by said live line stick and to be manipulated by an operator todisengage said movable current carrying member from said terminalcontact member while said shunt circuit is maintained, the connectionsbetween said auxiliary circuit interrupter and said terminal contactmember and between said auxiliary circuit interrupter and said movablecurrent carrying member being sufficiently flexible so that it isunnecessary to exert a pull on said live line stick in said plane ofmovement of said movable current carrying member or in a plane parallelthereto to manipuiate said auxiliary circuit interrupter, and means foroperating said auxiliary circuit interrupter to open said shunt circuitafter said movable current carrying member disengages said terminalcontact member.

23. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like, normallycarrying current and having a stationary normally energized terminalcontact member and a current carrying member movable into and out ofengagement therewith by manipulation of a live line stick, saidmechanism comprising, in combination, an auxiliary circuit interrupterhaving contact means for connection to said terminal contact member andadditional contact means for connection to said movable current carryingmember, said auxiliary circuit interrupter when closed providing a shuntcircuit between said terminal contact member and said movable currentcarrying member, said additional contact means including a flexiblymounted conducting member having a portion engaging said movable currentcarrying member and movable therewith as it moves away from engagementwith said terminal contact member, said auxiliary circuit interrupterbeing adapted to be carried by said live line stick and to bemanipulated by an operator to disengage said movable current carryingmember from said terminal contact member while said shunt circuit ismaintained, and means for operating said auxiliary circuit interrupterto open said shunt circuit after said movable current carrying memberdisengages said terminal contact member.

24. Mechanism for opening a high voltage circuit isolating device suchas a disconnecting fuse, disconnecting switch or the like, normaliycarrying current and having a stationary normally energized terminalcontact member and a current carrying member movable in a plane into andout of engagement therewith by manipulation of a live line stick, saidmechanism comprising, in combination, an auxiliary circuit interrupterhav- L19 ing contact means for connection to said terminal contact memer and additional contact :imeans 'for connection tosaid movable current'carrying member, said auxiliary circuit interiruptertwhen closedproviding a shunt circuit be- :tween said terminal contact member andsaid movable current carrying member, said auxiliary circuit interrupterbeing'adapted to be carried "by said live line stick andto bemanipulated by :an operator to disengage said movable current carryingmember from said terminal contact lmember whilesaid shunt circuit ismaintained, the connections between said auxiliary circuit in iterrupterandsaid terminal contact member and ibetwe'en said auxiliary circuitinterrupter and said :movable current carrying member being sufficientlyflexible to allow the manipulation of said live line stick with asubstantial range of movement in planes other than said plane of,movement of said movable current carrying memiber4andplanes parallelthereto, the connection "between said auxiliary circuit interrupter andisaidimovable current carrying member'including aiconducting'memberpivot-ally mounted with respect to'the former at one end and at theother fend-movable with said current carrying member as the samemoves insaidplane away from said tterminal contact member, and means foroperatzing'saidauxiliary-circuit interrupter to open said rshuntlcircuitafter said movable current carrying :member disengages said terminalcontact memiber.

'25. :Mechanismioropening a nigh voltage circuitisoiating devicesuchasadisconnecting fuse, disconnecting switch or the like, normally carryingcurrentand having a stationary normally aenergized terminal contact.member and a current carrying member a plane parallel thereto saidauxiliary 320 movable in a plane into'and out of engagement therewith bymanipulation'of a live line stick, said nrechanism comprising, incombination,an auxiliary circuit interrupterhaving contact means forconnection to said'terminal contact member andadditional contact meansfor connection to said movable current carrying member, said additionalcontact means including aconducting memberpivoted at one end 1m saidauxiliary circuit-interrupter and at'the other end adapted to belooselypivoted'to said current carrying member and movable therewith as.it moves in said plane awayifrom said terminal'co'ntact membensaidauxiliary circuit interrupter whenclosed providing a shunt circuitbetween said terminal contact member and said movable current carryingmember saidauxiliary circuit interrupter being adapted to be carried bysaid live line stick and to be manipulated by an operator to disengagesaid movable current carrying member from said terminal contact memberwhile said shunt circuitis maintained, the connections between said.auxiliary circuit interrupter and said terminal contact member andbetween said auxiliary circuit interrupter and said movable currentcarrying member-being sufilciently flexible so that it is unnecessary toexert a pull on said live line stickin said plane of movement of saidmovable current carrying member or in to manipulate saidauxiliarycircuit interrupter, and means for operating circuitinterrupter to open said shunt circuit after said movable currentcarrying member disehgagessaid terminal contact member.

SIGURD I. LINDELL 'No referencescited.

